Corporate Average Fuel Economy (CAFE) is the required average fuel economy, expressed in miles per gallon (mpg), for a vehicle manufacturer's entire fleet of passenger cars and light trucks with a gross vehicle weight rating (GVWR) of 8,500 lbs. or less, manufactured for sale in the United States, for any given model year. In April 2010, EPA issued the final rule applying to passenger cars, light-duty trucks, and medium-duty passenger vehicles, covering Model Years (MY) 2012 through 2016. These standards work towards achieving an average fuel economy of 34.1 miles per gallon by Model Year 2016 for cars and light-duty trucks. The Clean Air Act gives California special authority to enact stricter air-pollution standards for motor vehicles than the federal government's. NHTSA administers the CAFE program, and the EPA provides the fuel economy data. Under the 2010 CAFE rule, fuel economy standards are restructured so that they are based on a measure of vehicle size called "footprint," the product of multiplying a vehicles wheelbase by its track width. A target level of fuel economy is established for each increment in footprint. Smaller footprint light trucks have higher targets and larger ones, lower targets. In 2012, EPA and NHTSA issued a joint Final Rulemaking to extend the National Program of harmonized greenhouse gas and fuel economy standards to model year 2017 through 2025 passenger vehicles. MY 2025 vehicles are expected to emit one-half of the GHG emissions of a MY 2010 vehicle. The 2017-2025 standards are consistent with President Obama's agreement with thirteen major automakers to increase average fuel economy to 54.5 miles per gallon for cars and light-duty trucks by Model Year 2025.